What It Is

• dll_main_header : Required header files for WinAPI and ASM Definitions
• dll_main_source : Required DllMain api-entry-point. Its calling when DLL_PROCESS_ATTACH triggered from ASM.

Please see here for more information about DllMain WinAPI entry-point.

Syntax

BOOL WINAPI DllMain(
  _In_ HINSTANCE hinstDLL,
  _In_ DWORD     fdwReason,
  _In_ LPVOID    lpvReserved
);

• hinstDLL

• A handle to the DLL module. The value is the base address of the DLL. The HINSTANCE of a DLL is the same as the HMODULE of the DLL, so hinstDLL can be used in calls to functions that require a module handle.

• fdwReason

• The reason code that indicates why the DLL entry-point function is being called. This parameter can be one of the following values.

• DLL_PROCESS_ATTACH

• DLL_PROCESS_DETACH

• DLL_THREAD_ATTACH

• DLL_THREAD_DETACH

• lpvReserved

• If fdwReason is DLL_PROCESS_ATTACH, lpvReserved is NULL for dynamic loads and non-NULL for static loads.

• If fdwReason is DLL_PROCESS_DETACH, lpvReserved is NULL if FreeLibrary has been called or the DLL load failed and non-NULL if the process is terminating.

Main

BOOL APIENTRY DllMain(HANDLE hModule, DWORD  fdwReason, LPVOID lpvReserved) {
    switch( fdwReason ) {
        case DLL_PROCESS_ATTACH:
    
        case DLL_THREAD_ATTACH:
    
        case DLL_THREAD_DETACH:
    
        case DLL_PROCESS_DETACH:
     
    }
    return TRUE;
}

Examples

For an example, please see Dynamic-Link Library Entry-Point Function.